Hesa it ok for your hubby to go 15km in this climate but believe me in summer he will get roasted cycling in red hot burning sun.
Cycling in winter is ok but summer no way. Moreover cycling is dangerous as people in 4x4 dont care much about other small cars and specially bycycles on road.
No offence to 4x4 owners. Its kind of 4x4 culture. I will never prefer cycling on main roads specially in rush hours.

Peace.